Roadway detour system for vehicles

ABSTRACT

A system to direct a vehicle off a roadway when there is insufficient clearance between the vehicle and a nearby overpass includes a height sensing device in combination with a detour signal device that directs the vehicle off the roadway. The height sensing device transmits a beam of light across a roadway to a photocell. The beam of light is at a predetermined height over the roadway and is subject to interruption by a vehicle that exceeds this predetermined height. The detour signal device, which is located a predetermined distance from the height sensing device, is activated when the light beam is interrupted and directs the vehicle toward an exit from the roadway to an alternate safe route.

United States Patent [1 1 Rule [ ROADWAY DETOUR SYSTEM FOR VEHICLES [76]Inventor: Charles J. Rule, 2i [3 Stansbury, St. Louis, Mo. 63118 22Filed: July 11, 1973 211 Appl. No; 378,254

[52] US. Cl. 340/31 R; 250/222 R [5 1] Int. Cl G08g 1/04 [58] Field ofSearch 340/31 R, 38 P [56] References Cited UNITED STATES PATENTS3,275,984 9/1966 Barker 340/31 R FOREIGN PATENTS OR APPLICATIONS 420,393ll/l934 United Kingdom 340/38 P 1 July 22, 1975 Primary ExaminerWilliamC. Cooper Attorney, Agent, or Firm-John D. Pope, [ll

[57] ABSTRACT A system to direct a vehicle off a roadway when there isinsufficient clearance between the vehicle and a nearby overpassincludes a height sensing device in combination with a detour signaldevice that directs the vehicle off the roadway. The height sensingdevice transmits a beam of light across a roadway to a photocell. Thebeam of light is at a predetermined height over the roadway and issubject to interruption by a vehicle that exceeds this predeterminedheight. The detour signal device, which is located a predetermineddistance from the height sensing device, is activated when the lightbeam is interrupted and directs the vehicle toward an exit from theroadway to an alternate safe route.

9 Claims, 4 Drawing Figures ROADWAY DETOUR SYSTEM FOR VEHICLES Thisinvention is directed to new and useful improvements in traffic controlsystems and more particularly to a roadway detour system for directing avehicle to an alternate route when there is insufficient clearancebetween the vehicle and a nearby overpass or similar obstruction.

Almost every roadway in use today leads into tunnels or beneath bridges,traffic ramps, railway tressels and elevated highways, etc., all ofwhich can be generally referred to as overpasses. It is well known thatmany of these overpasses do not have sufficient height to safely clearunusually tall vehicles, particularly trucks.

Generally, signs or other warning devices are posted in advance of theoverpasses indicating the maximum safe vehicle height which the overpasscan safely accomodate. Despite such warnings, accidents due to insufficient clearance between vehicles and overpasses remain a continuingproblem.

Proposed solutions to this problem include providing radio transmitterson overpasses and equipping vehicles with special warning receivers.This is an expensive approach to the problem and would require thereceivers in moving vehicles to be in continuous operation. Anotherproposed solution includes equipping a vehicle with an overpassclearance detector switch operable to warn a driver of insufficientclearance when the vehicle is already at the overpass. This device doesnot solve the problem if the vehicle is traveling too fast to stopbefore the overpass. Furthermore, even if the vehi cle is safely stoppedin advance of the overpass. the driver is normally in an equallydangerous predicament of detouring his vehicle in the face of oncomingtraffic.

It is thus desirable to provide a roadway detour system for directingthe vehicle to a safe exit or detour from the roadway before the vehiclecomes to an overpass having insufticient clearance.

Among the several objects of the present invention my be noted theprovision of a novel roadway detour system for directing a vehicle awayfrom an overpass; a novel roadway detour system that does not requireinstallation of special equipment on those vehicles which the detoursystem is designed to protect; a novel roadway detour system that can beactuated into operation by a vehicle that will not safely clear a nearbyoverpass; and a novel detour system that forms a part of the roadwaysystem and is arranged to operate only when a vehicle exceeds apredetermined height. Other objects and features will be in partapparent and in part pointed out hereinafter.

The present invention relates to a novel roadway detour system having adetour signal which can be actuated into operation by a vehicle as itpasses a checkpoint, if the vehicle exceeds a predetermined height. Inone embodiment the invention comprises a device for sensing the heightof a vehicle in combination with a device for providing a detour signalwhen required.

The height sensing device which includes a light beam transmitter and alight sensing element produces a beam of light at a predetermined heightacross the roadway. A vehicle exceeding this predetermined height willinterrupt the light beam to activate the detour signal device.

The detour signal device comprises a signal light having those colorsconventionally used to slow down and- /or stop the movement of traffic.The detour signal lights can be arranged in the shape of arrows forexampie to direct the vehicle with excessive height to a roadway exit ordetour. A sound signal arrangement can be included in combination withthe signal lights.

The circuit networks for operating the height sensing device and thedetour signal device communicate with each other and derive their powerfrom the same power source. Power to the detour signal network is fedthrough a normally closed switch except when the switch is held in anopen position. The switch assumes its normally closed position whenreception of the light beam by the light sensing device is interruptedby a vehicle exceeding the predetermined height. A timing deviceincluded with the switch maintains the switch in its closed position fora predetermined time to provide a detour signal having a desired timeduration. Subsequent reception of the light beam by the light sensingdevice causes the switch to open and terminate actuation of the detoursignal device.

The height sensing device and detour signal device are spaced apart adistance that is compatible with the general speed of traffic on theroadway. This spacing ensures that a vehicle having excess height isgiven ample opportunity to be alerted by the detour signal device whenthe vehicle has interrupted the light beam. A roadway exit provided inthe vicinity of the detour signal device leads the alerted vehicle to analternate route such as a depressed service road providing adequateclearance between the vehicle and the overpass, or to any other suitabledetour.

The invention accordingly comprises the constructions hereinafterdescribed, the scope of the invention being indicated in the followingclaims.

In the accompanying drawings, in which several of various possibleembodiments of the invention are illustrated,

FIG. 1 is a side view of a roadway detour system incorporating oneembodiment of the present invention;

FIG. 2 is a plan view thereof;

FIG. 3 is a simplified schematic block diagram of the roadway detoursystem operating circuit; and

FIG. 4 is a simplified schematic block diagram showing anotherembodiment of my invention.

Corresponding reference characters indicate corresponding partsthroughout the several views of the drawings.

Referring to the drawings, a roadway detour system 10 incorporates oneembodiment of the present inven tion. Detour system 10 includes a heightsensing device 12 comprising any suitable known upright standard memberssuch as poles 14 and 16 spaced from each other on small islands 18 and20 located at opposite sides of a roadway 22. Poles l4 and 16 includeany suitable known means 24 for raising or lowering the pole height.

The upper end portion of pole 14 includes any suitable known light beamtransmitter 26 for transmitting a collimated beam of light 28 acrossroadway 22 at a desired predetermined height above roadway 22 whichheight is generally designated 29. Height 29 of light beam 28 ispreferably slightly less than the height of an overpass 30 extendingacross roadway 22.

The upper end of pole 16 includes any suitable known light receivingmeans such as a photocell 32. The beam of light 28 from transmitter 26is arranged to focus on photocell 32.

Detour system 10 further includes a detour signal device 34 comprisingany suitable known upright standard members such as poles 36 and 38spaced from each other on small islands 40 and 42 located at oppositesides of roadway 22. A cross member 44 extending across roadway 22 issupported at the upper portions of poles 36 and 38. Poles 36 and 38include any suitable known means 46 for raising or lowering the poleheight, and the height of cross member 44 over roadway 22 can bearranged to exceed the known maximum height of vehicles in current use.

Detour signal device 34 is located a predetermined distance from heightsensing device 12 based on the speed range and maximum stoppingdistances of traffic on roadway 22. Any suitable known detour signallights 48 are provided on cross member 44 and any suitable known soundsignal device 50 is likewise provided on member 44. Detour signal lights48 can be of those colors conventionally used to slow down and/or stoptraffic.

The operating circuit for detour system comprises any suitable knownpower source 52 connected to any suitable known normally closed switch54. Switch 54 is connected to any suitable known timing device 56 formaintaining switch 54 in a closed position. Switch 54 shown in openposition in FIG. 3, leads to sound signal 50 and detour signal lights48. Power source 52 is also connected to transmitter 26 but there is noelectrical connection between transmitter 26 and photocell 32. Photocell32 is connected to any suitable known amplifier 58 which amplifierelectrically communicates with any suitable known switch control means60 for maintaining switch 54 in an open position.

In use, roadway detour system 10 transmits light beam 28 fromtransmitter 26 to photocell 32. Photocell 32 is arranged in any suitableknown manner to convert light beam 28 to an electrical signal. Amplifier58 is arranged in any suitable known manner to amplify the electricalsignal from photocell 32. The amplified electrical signal from amplifier58 activates switch control means 60 to maintain switch S4 in an opencondition. Consequently, there is an open circuit between power source52 and signal devices 48,50 when light beam 28 is transmitted tophotocell 32.

Reception of light beam 28 by photocell 32 can be interrupted by a truck62 that passes between poles 14,16 and exceeds predetermined height 29of beam 28. Photocell 32 is thus prevented from producing an electricalsignal thereby deactivating switch control means 60. As a result, switch54 assumes its normally closed position permitting power to flow fromsource 52 to detour signal lights 48 and sound signal 50. Timer 56 isarranged in any suitable known manner to be activated when switch 54closes.

Timer 56 serves to maintain switch 54 in its normally closed positionfor a predetermined time duration after photocell 32 begins to againreceive light beam 28 from transmitter 26. Detour signal lights 48 andsound signal 50 are thus activated for the predetermined time it wouldnormally take to detour a vehicle that has actuated detour signal 34.

Detour signal lights 48 can be shaped as arrows that point to a roadwayexit or detour 64 provided near detour signal device 34. If desired,detour signal device 34 can also carry an illuminated message givingdetour directions. Detour 64 leads vehicle 62 away from overpass 30 to adepressed service road (not shown) that provides sufficient clearancebetween vehicle 62 and overpass 30, or detour 64 can lead to any othersuitable alternate route.

As will be apparent to those skilled in the art, height sensing device12 and detour signal device 34 can be supported or suspended from anyother suitable known support means besides poles. It will also beapparent that transmitter 26 can be arranged to transmit two collimatedlight beams spaced apart a predetermined distance such as shown at 28and 66 in FIG. 3.

Provision of light beam 66 in addition to light beam 28 can help guardagainst nonvehicular actuation of detour signal 34 as by a leaf or anyother randomly moving object that,might cross the path of a light beam.The spacing between beams 28 and 66 can be arranged to ensure that atleast one light beam is received by photocell 32 in the event of anundesired interruption of the other light beam.

Since more than one vehicle may be alerted or stopped by roadway detoursystem 10, detour signal device 34 can be arranged to carry a conciseilluminated or recorded message such as DANGER! Overpass Ahead. VehiclesExceeding 18 Feet Must Exit." Any other known visually attractive meansfor directing an endangered vehicle off the roadway can besimultaneously actuated in a known or previously described manner foroperation in combination with detour signal device 34.

Detour system 10 can be functionally arranged to extend across more thanone lane or roadway including lanes in which traffic moves in oppositedirections. For example, the height sensing device for detour system 10can include a plurality of spaced light beam transmitters 68, 70 and 72identical to transmitter 26, as shown in FIG. 4. Transmitters 68, 70 and72 transmit light beams 74, 76 and 78 to photocells 80, 82 and 84identical to photocell 32. The operating circuit for this modifiedroadway detour system can be arranged in any suitable known manner toactivate detour signal device 34 only when light beams 74, 76 and 78 areinterrupted in a predetermined sequence such as 74-7- 6-78.

In FIG. 4, traffic moving in one direction is symbolically indicated byarrow 86 and traffic moving in the opposite direction is symbolicallydesignated 88. An oversize vehicle moving in direction 86 will interruptthe light beams in sequence 74-76-78 and thereby activate detour signaldevice 34. Conversely, an oversize vehicle traveling in direction 88will interrupt the light beams in the sequence 78-76-74 thereby havingno effect on detour signal device 34.

Some advantages of the novel invention evident from the foregoingdescription include a roadway detour system that detours vehiclesexceeding a predetermined height to a roadway exit, a roadway detoursystem having a detour signal device that can be actuated into operationby a vehicle passing a check point in a given direction, and a roadwaydetour system that does not require installation of special equipment onthose vehicles which the detour system is designed to protect.

In view of the above, it will be seen that the several objects of theinvention are achieved and other advantageous results attained.

As various changes could be made in the above constructions withoutdeparting from the scope of the invention, it is intended that allmatter contained in the above description or shown in the accompanyingdrawings shall be interpreted as illustrative and not in a limitingsense,

What is claimed is:

l. A roadway detour system for vehicles comprising means for sensing theheight of vehicles in combination with means for providing a detoursignal, said height sensing means including means for transmitting alight beam at a predetermined height across said roadway, and lightsensing means for receiving the beam of light crossing said roadway,said light sensing means including a collimating member for collimatingsaid light beam, said detour signal means being connected to andoperable by said height sensing means and comprising a signal devicelocated between said height sensing means and a roadway exit, andnormally inactivated when said light beam is received by said lightsensing means, said roadway detour system further including means foractivating said signal device to produce said detour signal whenreception of said light beam by said light sensing means is interruptedby a vehicle having a height in excess of said predetermined height.

2. A roadway detour system as claimed in claim 1 further including anelectric power supply means and wherein said detour signal device iselectrically operable, said means for activating said detour signaldevice including switch means interposed between said power supply meansand said detour signal device, said switch means being in a first switchposition wherein said power supply means is isolated from said detoursignal device when said light beam is received by said light sensingmeans, and said switch means being in a second switch position whereinsaid power source is electrically communicative with said detour signaldevice through said switch means when reception of said light beam bysaid light sensing means is interrupted.

3. A roadway detour system as claimed in claim 2 wherein said switchmeans has an open position, and a normally closed position, said firstswitch position being the open position wherein said switch means opensthe circuit between said power supply means and said detour signaldevice, said second switch position being the normally closed positionwherein said power supply means communicates with said detour signaldevice through said switch means.

4. A roadway detour system as claimed in claim 3 fu rther including atiming device connected to said switch means for maintaining said switchmeans in said closed position for a predetermined amount of time whenreception of said light beam by said light sensing means is interrupted.

5. A roadway detour system as claimed in claim 1 wherein said detoursignal device produces a visual signal.

6. A roadway detour system as claimed in claim 5 wherein said detoursignal device further produces a sound signal.

7. A roadway detour system as claimed in claim I wherein said heightsensing means is spaced a predetermined distance from said detour signalmeans such that said vehicle when moving in a given direction approachessaid detour signal means after passing said height sensing means.

8. A roadway detour system as claimed in claim 1 wherein said lighttransmitting means are provided in a first upright member disposed atone side of said roadway, said light receiving means being provided in asecond upright member disposed at a second side of said roadway oppositethe first side of said roadway.

9. A roadway detour system as claimed in claim 1 wherein said heightsensing means includes means for varying the height of said lighttransmitting means and said light sensing means.

1. A roadway detour system for vehicles comprising means for sensing theheight of vehicles in combination with means for providing a detoursignal, said height sensing means including means for transmitting alight beam at a predetermined height across said roadway, and lightsensing means for receiving the beam of light crossing said roadway,said light sensing means including a collimating member for collimatingsaid light beam, said detour signal means being connected to andoperable by said height sensing means and comprising a signal devicelocated between said height sensing means and a roadway exit, andnormally inactivated when said light beam is received by said lightsensing means, said roadway detour system further including means foractivating said signal device to produce said detour signal whenreception of said light beam by said light sensing means is interruptedby a vehicle having a height in excess of said predetermined height. 2.A roadway detour system as claimed in claim 1 further including anelectric power supply means and wherein said detour signal device iselectrically operable, said means for activating said detour signaldevice including switch means interposed between said power supply meansand said detour signal device, said switch means being in a first switchposition wherein said power supply means is isolated from said detoursignal device when said light beam is received by said light sensingmeans, and said switch means being in a second switch position whereinsaid power source is electrically communicative with said detour signaldevice through said switch means when reception of said light beam bysaid light sensing means is interrupted.
 3. A roadway detour system asclaimed in claim 2 wherein said switch means has an open position, and anormally closed position, said first switch position being the openposition wherein said switch means opens the circuit between said powersupply means and said detour signal device, said second switch positionbeing the normally closed position wherein said power supply meanscommunicates with said detour signal device through said switch means.4. A roadway detour system as claimed in claim 3 further including atiming device connected to said switch means for maintaining said switchmeans in said closed position for a predetermined amount of time whenreception of said light beam by said light sensing means is interrupted.5. A roadway detour system as claimed in claim 1 wherein said detoursignal device produces a visual signal.
 6. A roadway detour system asclaimed in claim 5 wherein said detour signal device further produces asound signal.
 7. A roadway detour system as claimed in claim 1 whereinsaid height sensing means is spaced a predetermined distance from saiddetour signal means such that said vehicle when moving in a givendirection approaches said detour signal means after passing said heightsensing means.
 8. A roadway detour system as claimed in claim 1 whereinsaid light transmitting means are provided in a first upright memberdisposed at one side of said roadway, said light receiving means beingprovided in a second upright member disposed at a second side of saidroadway opposite the first side of said roadway.
 9. A roadway detoursystem as claimed in claim 1 wherein said height sensing means includesmeans for varying the height of said light transmitting means and saidlight sensing means.